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Transmission fluid flush

is a fluid flush (advertised by Jiffy lube) the same as a fluid change?
if not, is this a good way to go?
I have a 2002 ford explorer and the transmission has a hesitation (about 30 sec.) as soon as it is put in drive.

Avoid using the quick lube places especially for transmission service. Talk to friends or co workers and find out which mechanics they like to go to, or check out the mechanics files (link above) Flushes are generally not recommended, a change with a change/cleaning of the filter are a better way to go.

68, check the fluid level in your automatic cold with the engine running. If it’s full but, discolored i.e. really dark red or brown, you are starting to have a problem and any kind of fluid change or flush might not help. You’re starting to have hard seals inside you automatic. Once the transmission warms up a little, the seal starts to become flexible and the transmission goes into get. Some times, a flush might help but usually the symptom comes back. Might be rebuilding time. FYI, just a regular service is fine in the transmission is in good working order and the fluid still looks nice and red. It it’s starting to discolor, it best to have a complete flush to rid the transmission of all the bad fluid.

I suggest going to a trusted transmission mechanic since the issue may be more than a fluid problem. Jiffy might be able to do the flush correctly, but I wouldn’t be comfortable with them doing that job for me.

"might be able to do the flush correctly, but I wouldn’t be comfortable with them doing that job for me. "

I wouldn’t even be comfortable with them doing a routine oil change, and as a result, I wouldn’t even consider allowing a quick lube joint to do anything related to my transmission.

Instead, the OP should take his car to an independent transmission shop.
Just as I avoid quick lube places, I would also recommend that the OP avoid chain-run transmission shops, such as Lee Myles, Cottman, Mr. Transmission or (God forbid!) AAMCO.

Ask friends, neighbors, and relatives for the name of a trusted independent trans shop.

Transmission fluid flushes are usually discouraged here. For most vehicles, a proper service is best, which means dropping the pan, cleaning out the gunk, changing the fluid and the transmission filter.

A flush doesn’t do any of that. It doesn’t even change the fluid very well. A “flush” is done by connecting the flush machine in series with the transmission cooler lines. The idea is that as fluid is expelled by the transmission, that can be prevented from going back in, and new fluid can go back in instead. The problem is that fluid is constantly circulating from the pan to the cooler lines, but a lot of that fluid is pan fluid, and not coming from inside the transmission itself. So much the fresh, new fluid comes out of the flush machine, goes into the pan, which just goes back out the cooler line and into the flush machine to be discarded. It’s just not an efficient way to replace the transmission fluid. If they waited for most of the transmission fluid to come out and be replaced with fresh, they’d have to pump in many, many gallons of fresh fluid. Which of course – unless you agree to pay the cost of many, many gallons of fresh fluid – won’t be done.

You have two choices.

Either ignore the problem and let the transmission burn itself up, or have the transmission serviced to see if can be saved.

If it were brought my shop, here’s what I would do.

Remove the pan and drain the fluid.

Inspect the debris in the pan.

If any metal particulate is found, reinstall the pan and refill the transmission with fluid. The transmission is done.

If no metal particulate is found, I would then install a new filter and reinstall the pan.

I would then connect the transmission fluid exchange machine and exchange the transmission fluid.

I would then add an additive such as SeaFoam Trans Tune to the transmission fluid. This contains additives that reconditions the seals within the transmission.

Contrary to what @GeorgeSanJose has just stated, a transmission fluid exchange machine replaces 100% of the transmission fluid in the transmission.


Contrary to what GeorgeSanJose has just stated, a transmission fluid exchange machine replaces 100% of the transmission fluid in the transmission.
‌ I'd place my money on @Tester. He's most likely correct, he's a pro, I'm just a DIY'er. And I've never even seen a transmission flush done.

For clarity though, here’s where I saw that info about a flush not replacing all the fluid.

"Proponents of transmission flushing often claim 100% of the fluid is replaced

This is untrue for several reasons. When the engine is running and the transmission is in park, only a part of the fluid is circulated. A good deal of fluid simply flows from the pump back to the pan, through the pressure relief valve. Several components in the pressure circuit do not receive flow at all."

Tester, a 100% exchange only occurs when it is done as you describe.

The fluid is sucked up through the filter in the center of the pan, goes through the valve body, torque converter and other required places in the transmission and then all of it goes to the cooler, unless there is an blockage in the cooler, then there is a bypass valve if needed.

The fluid is returned to the pan. If the pan is not drained and/or dropped, then the fluid is diluted by the exchange machine and a 100% exchange does not occur. Dirty fluid is drawn from the center of the pan and fresh added near the edge. The longer you do this and the more ATF you use in the process, the more you dilute the dirty ATF with fresh ATF, but you never get it all.

Other than being in agreement with others, I might add that a 30 second delay does not sound good. A second or two is one thing; half a minute quite another, so the trans could be on the way out.

Sometimes the pan will get gunked up with debris and when the engine is running that debris will get pulled up against the screen and block fluid flow which just makes the problem even worse.
If the pan is gunked up that bad then the trans is likely on the last leg anyway.

Let me ask you this.

If you operate the exchange machine until the fluid coming out of the transmission is the same color as the new fluid going into the transmission, has 100% of the fluid been exchanged?


No, not if you didn’t drop or drain the pan. If you stuck a garden hose in one end of your swimming pool and a drain at the other, would you ever get a 100% exchange of the water? The dirty water will eventually get a little cleaner, but it never achieves 100% exchange.

Didn’t I say I would drop the pan?


Is it a full moon tonight? Seriously, your going to argue with @Tester on this?

I want to share the answer I received from a certified mechanic I know. He told me that the flush method is not very good, especially if you have trans problems. He stated that only a drain and filter is the only way.

Running the trans in park is never going to remove the fluid from the torus of the torque converter, that only mixes when the car is driven. A drain and fill doesn/t remove fluid from the converter either but at least you can change the filter and clean and inspect the pan.

The best way would be to have carmakers put the 5 cent pipe plug back in the torque converter.

That’s why some automatic transmissions have to be shifted into drive before the the pump within the transmission will transfer the fluid into the exchange machine.


I don’t like the idea of “transmission flushes” or “transmission fluid exchanges.” The old tried and true method of dropping the pan, replacing the filter and transmission fluid is good enough for me. I also would advise you never to darken the door of any chain shop, Jiffy Lube especially, for anything automotive related.

@68grandpa‌, you need to tell us what you are driving - brand, model, engine, and year. Mileage would help too. Some transmissions don’t have a pan, some do.

And didn’t I say

“Tester, a 100% exchange only occurs when it is done as you describe”

I was trying to point out that you were right when done your way, George was right when the pan is not dropped or drained.

missileman is also correct as long as the ATF is changed on a regular basis, 30-40k or so. If you don’t follow the schedule and the ATF has turned brown (or worse), then an exchange machine (properly done with a pan drop or drain) or four back to back changes are in order.